1. Field of the Invention
The subject invention generally pertains to water control valves and more specifically to a system for automatically closing a valve in response to sensing a flooding condition.
2. Description of Related Art
Various systems have been developed to prevent flooding caused by a leak in a building""s plumbing system. Without flood protection, even a small leak in a water line, water heater, or washing machine can cause substantial damage to a home if the leak occurs while the family is gone on vacation or if the house is left vacant for another reason. Thus, flood prevention systems preferably operate reliably and without attendance 24 hours a day, seven days a week for months or even years.
If a normally open valve is used to shutoff the water supply in response to a leak, it may be years before the valve is ever energized. During the extended period of inactivity, working members of the valve may deteriorate or become jammed with hard water deposits, and the problem may not be discovered until flooding occurs.
If a normally closed valve is used, the valve may need to be kept energized continuously for years, which could make a battery-operated system impractical. If a power failure occurs, the valve may close and leave a family without water as well.
If a flood prevention system includes a moisture sensor, the method of mounting such a sensor can be important. If the sensor is simply placed on the floor, the sensor may get washed away or otherwise dislodged. On the other hand, if the sensor is permanently attached to the floor, routine mopping of the floor may trigger the system, and the sensor may be difficult to dry until the floor dries.
To provide an improved flood prevention system, an object of some embodiments is to minimize the power consumption of the overall system.
Another object of some embodiments is to use a shutoff valve with a solenoid having two equilibrium positions, whereby the valve can maintain its open and closed positions without electrical current.
Another object of some embodiments is to provide a flood prevention system that uses such a minimal amount of current that the system can be battery operated.
Another object of some embodiments is to use a touch-and-hold fastener for removably attaching a moisture sensor to a floor.
Another object of some embodiments is to use an adhesive to hold a portion of the touch-and-hold fastener to the floor.
Another object of some embodiments is to provide a moisture sensor with a screw-receiving hole that offers second choice of attaching the sensor to the floor.
Another object of some embodiments is to periodically cycle the shutoff valve of a flood prevention system to help clear the valve of any hard water deposits.
Another object of some embodiments is to open and close a solenoid valve by simply reversing the polarity of the voltage used for actuating valve.
Another object of some embodiments is to minimize the electrical power required to actuate a valve by using a valve that is pilot operated.
Another object of some embodiments is use a valve having a diaphragm that is more flexible than hard water deposits, whereby the hard water deposits may tend to break off and separate from the diaphragm.
One or more of these and other objects of the invention are provided by a flood prevention system that includes double-latching shutoff valve that responds to a moisture sensor. To minimize a buildup of hard water deposits, the valve includes a flexible diaphragm and is cycled periodically. The sensor includes multiple methods of mounting to a floor.